Apparatus for producing and feeding paper pulp



May 1, 192-8. 1,668,141

R. S. CLARKE APPARATUS FOR PRODUCING AND FEEDING PAPER PULP Filed Oct. 12, 1922 3 Sheets-Sheet 1 I? /mE1 @ZHE D D I a a i I; f i 1 gnoenfoc 7fizbfi Sum Claw/5a, I- Q 1 I O 35% M M I I Qtfozueq)! May 1, 192 8. 1,668,141

R. s. CLARKE APPARATUS FOR PRODUCING AND FEEDING PAPER PULP Filed Oct. 12, 1922 3 Sheets-Sheet 2 May 1, 1928. 1 v 1,668,141

R. S. CLARKE APPARATUS FOR PRODUCING AND FEEDING PAPER PULP Filed Oct. 12, 1922 ISSheets-Sheet I5 :4 2 27/. 6. WIN 2 1 gwvcnhw, k fialjJ/a Swan Claw/(c,

Patented May 1, 1928.

UNITED STATES PATENT OFFICE.

RALPH SWAN CLARKE, OP WALPOLE, MASSACHUSETTS, ABSIGNOB TO BIRD MACHINE COMPANY, A CORPORATION OF MASSACHUSETTS.

a ncauon m October 12, 1022. Serial no. 594,076.

This invention pertains to an improved method of and apparatus for the production and feeding of paper pulp to paper making machines, and has for its main object the provisions of means whereby a large amount or volume of water, much in excess of that employed with any installation of which I am aware, may be utilized in a screen for cleaning the pulp, and the surplus water extracted from the pulp to reduce the same to the desired consistency after it leaves the screen and prior to its being fed or passed to the paper making machine proper.

In the continuous manufacture of paper of uniform grade, it is essential that the stock or pulp be clean, and this cleaning may be accomplished by various means, as, for instance, in screens of the rotary type, such as are depicted in U. S. Letters Patent 1,210,906, R. D. Clarke, dated January 2, 1917, and 1,304,253, Charles S. Bird, dated May 20, 1919. The invention hereinafter set forth and claimed is shown in connection with such a screen, that is to say, a screen of the rotary type, and reference is made to the aforesaid patents for a detailed description of such a screen.

The apparatus here involved may be said to comprise a-screen of the rotary type, from which the ulp with an excess of water therein, is dischar ed into a vet or receptacle in which a ewatering means is employed, in this instance, a rotar screen, and from which vat or receptacle t e dewatered pulp, or the pulp reduced to the proper consistency, is discharged or passes into the head box of a paper-making machine.

One embodiment of the invention is shown in the accompanying drawings, wherein,

Fig. 1 is a vertical longitudinal sectional view of the apparatus; 7

Fig. 2 an enlarged end elevation of the dewatering vat showin the discharge opening leading from the ewatering device or screen;

Fig. 3 a vertical sectional view of the dewatering screen at the discharge end thereof, the section being taken on the line IIIIII of Fig. 4;

Fig. 4 a top plan view of the dewaterin screen and the vat in which it works, an the head box;

Fig. 5 a transverse vertical sectional view taken on the line VV of Fig. 4; and

Fig. 6 a detail sectional view of the discharge end of the dewatering screen.

Referring to said drawings, 1 denotes the rotary pulp screen mounted to rotate within a vat 2, the screen being submerged throughout the major portion thereof. An oscillating or shaking motion is imparted to the vat to cause a surge of the pulp in the vat with reference to screen to cause the pulp to pass inwardly into the screen, all in a manner as set forth in the patents above specified. The usual shower pi es and water collecting troughs are shown, ut form no part of the present invention.

The discharge mouth of the cleaning screen .1, which mouth is denoted by 3, stands adjacent one side of a trou h 4, the mouth being partially cut off from the trough by dam boards 5 which control the flow of the cleaned pulp with the excess of water therein into the trough, and likewise control the correct level of the pulp in the cleaning screen and its vat. At the opposite side of the trough 4 there is located a dam or weir 6, adjustable as to height, and over which the dewatered pulp, or the pulp which is reduced to the proper consistency, flows into the head'box 7 of a paper-making machine, whence it passes, in the usual way, to a paper-making machine of any approved type.

In Fig. 1 there is indicated a roll 8 of the paper making machine, in order that the relationship of the various portions of the apparatus" may be clearly understood.

Located adjacent the intake end of the trough 4, or adjacent the dam 5, is a bafile board 9 which extends entirely across the trough from end to end, and from the top to a point adjacent the bottom of the trough, so as to produce a passage 9 between the lower end of the battle and the bottom of the trough, whereby the pulp as it asses from the cleaning screen, will be distri uteil and deflected into the bottom of the trough, thus preventin a direct current through the trough an an accumulation of dead stock therein.

Mounted in the upper portion of the trou h 4 is a dewatering or filtering element, whifii, in the instant case, takes the form of a rotary screen closed at one end and open at the other, and into which the excess water drains owing to the slight pressure which obtains upon the lower portion of the screen due to the submergence of the screen in the pulp. Mounted in suitable bearings at the ends of the trough 4 is a shaft 10, upon which is secured a series of spiders or open wheel-like elements 11, to the periphery of which there is attached a sheet of perforate metal 12 having relatively large openings 13 formed therein. This forms a drum-like element upon which is imposed a wrapping of wirecloth 14, having a relatively open mesh, say #14, and upon this there is lai an outer covering of finer mesh wire cloth 15,'say about #20 mesh.

One end of the rotary screen thus formed is closed by a head 16 (Fig. 4). The opposite end is open and stands adjacent. to an arcuate shaped member 17 L-shape in cross section, and secured to the inner face of the end wall of the trough. A discharge opening 18 stands in line with the lower portion of the screen so that any water passing into the screen will be discharged freely there from. In order to prevent the pulp from passing into the open end of the screen, I employ means coacting with the outer spider or member 11 and the arcuate member 17, which, in the present instance, takes the form of a band 19 fixed at one end on a pin 20 secured in a bracket 21 attached to the upper edge of the wall of the trough 4,'the band bein provided with a liner or facing 22 of suita le material which takes against the outer face of the curved or arcuate member 17 and the outer face of the member 11. Proper tension is maintained upon the band by means of a threaded extension or arm 23 which passes freely through an eye formed in a post 24 mounted in a fixed bracket 25. A wing nut 26 threaded upon the upper end of the arm 23 admits of proper ad ustment of the band, and, consequently its liner 22, against the face of the fixed member 17 and the outer face of the adjacent spider member 11. Clean out openings 27 are preferably providedat each end of the trough 4 in order thatthe trough may be cleaned out from time to time, as occasion may require.

A shower pipe 28 will be provided for the rotary dewatering screen, .and while I 1 have shown this pipe as being located exteriorly thereof, it ma be located interiorly provided a screen of t 1e type shown in connection with the cleaning screen be substituted for that above described.

In operation, the' ulp to be cleaned and fed to the paper-ma ing machine is passed to'the vat 2 along with an excess of water, or an excess of Water ma be supplied to the screen independently o the pulp, and is therein treated and separated in the usual manner, as obtains with screens of this type.

The cleaned pulp with an excess of water passes over the dam 5 into the trough 4 and beneath the bafile 9 to a point below the screen, the bafile tending'to roperly distribute the pul throughout t e length f the trough so t at the pulp will pass alike to all portions of the dewatering screen. The dewatering screen, as above noted, is rotated and the excess water in the pulp passes through the screen surface to the interior of the screen, thence out through the open end where it is discharged through the opening 18. The pulp thus thickened finally flows over the weir 6 into the head box 7 and thence to the paper making machine proper.

As before noted, to secure the maximum efliciency of the rotary pulp cleaning screen 1, it is necessary to maintain the correct level of the pulp in the vat. This, as also indicated above, is brought about. by the use of the dam 5. It may, however, be desir able to run a lower level in the trough 4 where the thickener or dewatering screen is placed. This is allowed of by varying the height of the weir or dam 6. "It is manlfest that in so far as the broad invention is concerned, a dewatering element of a construction other than that above set forth. and described may be employed, and in so far as the generic invention is concerned, I do not de sire to be limited either in the employment of a particular form of cleaning screen or a particular form of dewatering device.

What is claimed is,

1. In an'a paratus for cleaning paper pulp and feeding'the same to a paper-making machine, the combination of a vat; a

.rotary screen located in the vat and adapted to be partially submerged in the paper stock fed to the vat, said screen being open at one end for the discharge of the cleaned pulp which passes inwardly into the same; a trough located adjacent the discharge end of the screen; a dam controlling the outflow of the cleaned pulp from the screen into the vat; a dewatering device located in the upper ortion of the trough; and a weir located at t e discharge end of the trough, over which the thickened pulp may flow.

2. In an apparatus for cleaning paper pulp and feeding the same to a paper making machine, the combination of a'vat; a screen mounted within the vat and adapted to be partially submerged in the pa er stock placed within the vat, one end of the screen being open, and through which the cleaned pulp which passes inwardly into the screen from the vat is discharged; a trough located adjacent the discharge end of the screen; means for regulating the level of the stock within the vat and controlling its discharge into the trough; a rotatable cylinder placed in the upper portion of the trough, said cylinder being provided with a filtering surface which permits the passage of water inward- 1y into the screen, one end of the screen being open to admit of the discharge of water which passes into the same; and an adjustable weir located at thedischarge side of the trough and over which the pulp, from which the water has been partially'extracted, may ass. Y

3. u an apparatus for cleaning paper pulp and feeding the same to a paper-making machine, the combinationof a vat; a rotary screen located therein, one end of the screen being open; a trough located adjacent said open end and adapted to receive .the cleaned pulp from the cylinder; a dam con trolling the level of the stock in the vat and its discharge from the mouth of the screen into the vat; a-baflle'mounted in the trough adjacent said dam, said'baflie causing a downflow of the pul beneath its lower edge, and a consequent distribution of the pulp throughout the length of the trough; a rotary drum-like member mounted in the up-v per, portion of the trough; a filtering surface carried u on said drum-like member; an adjustable weir located at the discharge side of the trough and over which the pulp, from which the water has been partially withdrawn by said rotary drum-like member, may as to the paper-making machine.

4. n an apparatus for cleaning paper pulp and feeding the same to a paper-maklng machine, the combination of means for cleaning pulp in the presence of an excess of water; a trough into which said pulp is discharged alon with said excess of water; a rotary drumike member located in the upper portion of the trou h, said trough being provided at one en with a discharge opemngyin line with the lower portion of the drum-like member; an arcuate member secured to, the inner face of the end of the trough and extending below and uswardly from each side of the opening; an means for eflecting a ti ht jointbetween'said member and the en of the drum-like member to revent ingress of water or pulp into 'sai open end of the screen while still admitting. of free rotation of the drum-like memher.

In testimony whereof I have signed my to .name to this s ecification. 

